• Journal of Microbiology and Biotechnology
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• 제9권5호
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• pp.534-540
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• 1999

Thirty-seven strains of Bacillus thuringiensis were isolated from Korean soil and examined for H-antigen serotyping, toxicity, and different spectra of biological activities. The isolate HL-175 bore a specific H-antigen, different from the 51 known serotypes, a spherical $\delta$-endotoxin crystal, and minor different biochemical characteristics. It was resistant to ampicillin, colistin, and penicillin G. Therefore, it was classified as a new serotype, H52, with the name kim. The other 36 isolates also produced endotoxin crystals and endospores. The crystal shape of eight strains was cuboidal while the others were bipyramidal. Biochemical characteristics of the isolates were only slightly different from the known serotypes of B. thuringiensis. The flagellar (H) antigens of the 36 isolates were identified as: one colmeri (H21), three galleriae (H5a,5b); two pakistani (H13); one toumanoffi (H11a, 11b); and twenty-nine kurstaki (H3a,3b). All 36 isolates were resistant to ampicillin, colistin, penicillin, cephalothin, and chloramphenicol.

• 대한수의학회지
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• 제57권4호
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• pp.235-243
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• 2017

Salmonella (S.) Typhimurium is highly contagious, and its infection may rapidly spread within pig populations of herd. According to the survey (1,191 pigs) from 2003 to 2012, 155 pigs (13.0%) were diagnosed as salmonellosis in Jeju. Major porcine salmonellosis cases (88.4%) were concentrated in 4- to 12-week-old weaned pigs, but 6 pigs (3.9%) under 4 weeks old were also diagnosed. Based on the histopathologic examinations, ulcerative enteritis (63.9%) in the large intestine and/or paratyphoid nodules formation (57.4%) in the liver were most prevalent lesions in porcine salmonellosis. Single infection of S. Typhimurium and mixed infection with more than 2 pathogens were detected in 38 (24.5%) and 117 (75.5%) in pigs, respectively. Co-infections of Porcine reproductive and respiratory syndrome virus and Porcine circovirus type 2 were very common in porcine salmonellosis in Jeju and detected in 84 (54.2%) and 59 (38.1%) pigs, respectively. Based on the serotyping tests using 41 bacterial isolates, S. Typhimurium and S. Rissen were confirmed in 39 (95.1%) and 2 (4.9%) cases, respectively.

• 대한미생물학회지
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• 제22권4호
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• pp.413-425
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• 1987

In the present experiments, isolated Vibrio species from marine and clinical specimens from July, 1985 to October, 1986, had the results as follows: 1. The 55 strains of Vibrio were isolated and identified; Vibrio parahaemolyticus was 35 strains, Vibrio vulnificus was 10 strains, Vibrio alginolyticus was 10 strains. 2. In the K-serotyping of Vibrio parahaemolyticus, fourteen serotypes identified but three were not strains typable by the availble K-antisera. 3. In the Kanagawa phenomenon experiment of Vibrio parahaemolyticus, it proved positive reaction, 14 of 15 strains(93%) isolated from the patient and 13 of 20 strains(65%) isolated from the nature. 4. In twelve antibiotic resistance experiments, Vibrio parahaemolyticus and Vibrio alginolyticus showed 100% resistance on ampicilline, but Vibrio vulnificus showed 100% sensitivity. But all of them proved 100% sensitivity on chloramphenicol, tetracycline, nalidixic acid. 5. In the antibiotic resistance patterns, Vibrio parahaemolyticus proved that 15 strains(43%) resisted on 4 antibiotics and 5 strains(14%) resisted on 7 antibiotisc and. Vibrio vulnificus proved that 1 strain(10%) resisted on 2 antibiotics and 6 strains(60%) without resistance, Vibrio alginolyticus proved that 7 strains(70%) resisted on 3 antibiotics and 2 strains(20%) resisted on 8 antibiotics.

• Journal of Dairy Science and Biotechnology
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• 제18권1호
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• pp.47-60
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• 2000

Over decades of work, the probiotic research has grown rapidly with a number of new cultures, which is claimed a variety of benefit. However, many of the specific effects attributed to the ingestion of probiotics remain convoluted and scientifically unsubstantiated. Accordingly, the scientific community faces a greater challenge and must objectively seek cause and effect relationships for many potential and currently investigated probiotic species. Rational selection and design of probiotics remains an important challenge and will require a solid information about the physiology and genetics of candidate strains relevant to their intestinal roles, functional activities, and interaction of with other resident micro flora. As far as beneficial culture of lactic acid bacteria (LAB) is concerned, simple, cost-effective, and exact identification of candidate strains is of foremost importance among others. Until recently, the relatedness of bacterial isolates has been determined sorely by testing for one or several phenotyphic markers, using methods such as serotyping, phage-typing, biotyping, and so forth. However, there are problems in the use of many of these phenotype-based methods. In contrast, some of newer molecular typing methods involving the analysis of DNA offer many advantages over traditional techniques. These DNA-based methods have the greater discriminatory power than that of phenotypic procedures. This review focuses on the importance and the basis of molecular typing methods along with some considerations on de-sign and selection of probiotic culture for human consumption.

• Journal of Microbiology
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• 제43권5호
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• pp.424-429
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• 2005

In previous studies, it has been reported that both S. enteritidis, the most common serotype, and S. enteritidis Phage Type 4 (SEPT 4) isolates were identified as the most prevalent PT in domestic poultry and also in humans in Korea until 2002. The aim of this study was to analyze the genetic diversity and epidemiological properties of both PT isolates, and also to trace the source of SEPT 4 isolates from domestic poultry and humans by Pulsed-field gel electrophoresis (PFGE). In order to understand the molecular epidemiologic properties of SEPT 4 isolates, which have very similar phenotypic properties to our preliminary investigations (serotyping, phage typing, large plasmids and antibiograms), PFGE analysis with XbaI enzyme was performed on the representative SEPT 4 isolates. Thirty-six SEPT 4 isolates were analyzed and differentiated with 10 pulsed-field profiles (PFP) expressing very high discriminative ability (SID: 0.921). In PFP, SEPT 4 isolates from human patients showed a perfect genetic match with those from broiler chickens and meats. Therefore, this study was able to successfully trace the major source of SEPT 4 isolates and also to determine the usefulness of the PFGE method for genetic analysis of epidemic strains.

• Fisheries and Aquatic Sciences
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• 제26권10호
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• pp.605-616
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• 2023

Scuticociliatosis, caused by the parasitic pathogen Miamiensis avidus, poses a significant threat to olive flounder farms in South Korea. Infected fish suffer from severe systemic infections affecting various organs, with potential secondary bacterial diseases. This study investigated the emergence of different M. avidus serotypes in 20 olive flounder farms on Jeju island, South Korea, from 2015 to 2020. Additionally, we identified Tenacibaculum maritimum as a co-infecting bacteria. Based on serotyping and monitoring data, we developed a trivalent vaccine targeting two serotypes of M. avidus and one strain of T. maritimum. The efficacy of the vaccine was evaluated under laboratory conditions and demonstrated a relative percentage of survival (RPS) of 75%, 80%, and 93% for M. avidus serotype I, M. avidus serotype II and T. maritimum, respectively. Furthermore, successful field trials conducted on four different olive flounder farms resulted in significantly higher survival rates (52%-76% RPS) and weight gains in vaccinated fish. Overall, this study presents an effective vaccine against M. avidus and T. maritimum infections in farmed olive flounder, making a valuable contribution to sustainable aquaculture in South Korea.

• Fisheries and Aquatic Sciences
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• 제5권2호
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• pp.79-86
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• 2002

Listeria spp. were isolated from the samples submitted from various seafood plants such as raw materials, products, swab samples of plants floor and conveyor belts through the whole processing procedures. All the samples were collected from 3 kinds of seafood plants such as a imitation crab meat plant, jeotgal plant and frozen seafood plant. And also serotypes of the identified L. monocytogenes were determined. Among the 301 strains of isolated Llsteria spp., 96 strains, 179 strains and 26 strains were identified as L. monocytogenes, L. innocua and L. welshimeri, respectively. While among the 145 strains of Listeria spp. isolated from the imitation crab meat plant, $74\;(51.0\%)$ strains, $64\;(44.1\%)$ strains and $7\;(4.8\%)$ strains were identified as L. monocytogenes, L. innocua and L. welshimeri, respectively. In the case of the 126 strains of Listeria spp. isolated from the frozen seafood plant, $22\;(17.5\%)$ strains of L. monocytogenes,$93\;(73.8\%)$ strains of L. innocua, and $11\;(8.5\%)$ strains of L. wdshimeri were detected. Among the 30 strains isolated from a jeotgal plant, $22\;(73.3\%)$ strains of L. innocua and $8\;(26.7\%)$ strains of L. welshimeri were detected. The detection rates of L. monocytogenes, one of the very important food poisoning bacteria especially in frozen and/or refrigerated seafoods, were relatively high as $77.1\%$ (74/96 strains) in a imitation crab meat plant and $22.9\%$ (22/96 strains) in a frozen seafood plant, but not detected from jeotgal plant. Distribution of L. monocytogenes serotypes and characterization were examined. The serotypes of 96 L. monocytogenes isolated from pork skin, pork fat, the floor and conveyor belts were 1/2a $(59.4\%)$, l/2b $(6.2\%)$, 1/2c $(12.5\%)$ and unknown serotypes $(21.9\%)$. Unknown serotypes were divided into three specific groups by the O antigen they have.

• 대한수의학회지
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• 제27권2호
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• pp.227-233
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• 1987

This study was conducted to determine the epidemiological characteristics of Campylobacter enteritis. A total of 187 fecal specimens of Korean native goat were examined for the presence of C. jejuni and C. coli by direct plating. Fifty strains isolated were examined for biochemical and serological properties and susceptibility to 19 chemotherapeutic agents. A total of 29(15.5%) C. jejuni and 21 (11.2%) C. coli were isolated from the fecal specimen of 187 Korean native goats. Of the 50 isolates of C. jejuni and C. coli, 29 isolates of C. jejuni grouped as 7 biotypes (1,2,3,4,6,7 and 8) and biotypes 1(34.5%), 2(17.2%) and 3(20.7%) were encountered most frequently. Twenty-one C. coli strains were differentated into biotype I (61.9% of the isolates) and biotype II (38.1%). Of the 29 C. jejuni strains examined, 24(83.0%) were typable by the Lior serotyping scheme and five isolates were non typable. C. jejuni grouped as 8 serotypes, serotype 4(24.1%) and 26(20.7%) were encountered most frequently. In the case of 21 strains of C. coli grouped as 6 serotypes, the most frequent serotypes were 21(28.6%) and 25(23.8%). Total of 50 strains of isolated were all susceptible to amikacin, clindamycin and tobramycine. Overall 85% of isolates were sensitive to erythromycin, doxycycline, chloramphenicol, flume-quine, kanamycin, gentamicin, nalidixic acid, polymyxin B, colistin, tetracycline and ampicillin, but about 65% of isolates were resistant to cefamandole and ethyl hydrocuprein hydrochloride.

• Journal of Periodontal and Implant Science
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• 제25권1호
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• pp.89-98
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• 1995

P. intermedia are considered an important pathogen in adult periodontitis, rapidly progressing periodontitis, refractory periodontitis, pregnancy gingivitis, acute necrotizing ulcerative gingivitis, pubertal gingivitis. So far 2 DNA homology groups and 3 serotypes of P. intermedia have been reported but there is no data available as yet regarding genetic diversity for the species P. intermedia. The purpose of this study is to investigate, using bacterial DNA restriction endonuclease analysis, genetic diversity between individual strains of P. intermedia which are indistinguishable by serotyping and biotyping, occurrence of an intrafamilial transmission and genetic heterogeneity between P. intermedia strains isolated within a patient and within the same serotypes. The families who have had no systemic disease, no experience of periodontal treatment for the previous 1 year and no experience of antibiotics for the previous 6 months were selected and subgingival plaque was collected at 4 sites in each person and incubated in the anaerobic chamber. P. intermedia were identified by colony shape, gram stain, biochemical test, SK-I03(Sunstar Inc.) test and IIF using monoclonal antibody was perfomed for the determination of serotypes. P. intermedia strains were grown in BHI broth and whole genomic DNA was extracted and digested by restriction endonuclease. The resulting DNA fragments were separated by agarose gel electrophoresis, stained and photographed under UV. As the results of this study, intrafamilial vertial transmissions could be assessed in 2 families and horizintal transmissions in another 2 families. There were different DNA digest patterns within a patient, so P. intermedia showed that individuals could be colonized by multiple clonal types at anyone time. And different serotypes could be found within a patient and in the same serotype within a patient, obvius genetic heterogeneity could not be assessed. But in the same serotype in different famies, there were differences in the DNA digest patterns.

• 대한미생물학회지
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• 제15권1호
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• pp.3-8
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• 1980

Yersinia enterocolitica has been known to be an important enteric pathogen especially in Scandinavian countries and Canada. In Korea, the authors reported the first case of Y. pseudotuberculosis septicemia in 1979. In 1980, three isolates of Y enterocolitica were obtained from 3 adult patients with enteritis, besides the already reported one in a 5-month-old child, during March to June 1980. Difficulty in the isolation was experienced; ie., the organism was isolated only from the SS primary isolation plate in one case and in the other two cases only from the SS plates inoculated with overnight culture of selenite broth. The isolates showed typical cultural and biochemical characteristics except for the nonmotility even at room temperature. Two isolates were indole negative possibly belonging to Wauter's biotype 3 and the other one was indole positive belonging to biotype 2. One patient was tested for the serum agglutinin titer on the 8th hospital day and it was found to be 1:128. All of the isolates were susceptible to chloramphenicol, colistin, gentamicin, kanamycin, tetracyclne, and tobramycin by the Kirby-Bauer disc diffusion method. All of the infections were controled by ampicillin, amoxicillin, amikacin, or gentamicin treatment. It is considered urgent to broaden our knowledge on yersiniosis in Korea not only by isolating, serotyping and biotyping of the organism, but also by surveying serum agglutinin titer of enteritis patients and normal individuals.